I was thinking kind of building 2 cities with no griefing in them, number 1: The City of (Name ideas) and number 2: The Forgotten City of the Ancients.
Number 1 will have shops and houses to either buy or steal from and being caught will make you lose your inventory of items and jailed for like.. 1 minute lol. and it is pvp but guards will come and attack the player who hit first.
Number 2 will be ruins with vines spreaded throughout and most likely very dark with spawners and traps that can be reset. It will have chests that have items in them deep in the dungeons and ruins that will be replaced with items if raided, and also you won't be able to quickly teleport out. Its pvp but you can't grief.
This was just my ideas but yeah